摘要：制备低成本的高效电催化剂是缓解目前面临的环境能源危机的重要方式.通过无定型化和构建异质结构可以有效地改变催化剂的电子结构,从而实现电催化性能的稳步提升.但是对于两者之间协同作用的研究则相对较少.在本文中,我们构建了富含异质结构的无定型FeMo基(a-FeMo)电催化剂,并系统评估了该催化剂的氮气还原和析氧反应性能.得益于无定型结构引起的活性位点数目的增多和异质结构引发的电子的重新分布,a-FeMo催化剂表现出优异的电化学催化性能.在-0.1 V ***的电势下,a-FeMo催化剂表现出29.15%的法拉第效率和71.78μg_(NH_(3)) mg_(cat.)^(-1) h^(-1)的氨气产率.这为合理设计具有低成本优势、高活性和长时间稳定性的优异催化剂提供了有益的参考.

摘要：Background Chronic obstructive pulmonary disease(COPD)is a severe public health *** smoke(CS)is a risk factor for COPD and lung *** underlying molecular mechanisms of CS-induced malignant transformation of bronchial epithelial cells remain *** this study,we describe a lung-on-a-chip to explore the possible mechanistic link between cigarette smoke extract(CSE)-associated COPD and lung *** An in vitro lung-on-a-chip model was used to simulate pulmonary epithelial cells and vascular endothelial cells with *** levels of IL-6 and TNF-αwere tested as indicators of inflammation using an enzyme-linked immune sorbent *** junction complex mRNA expression was detected with qRT-PCR as the index of epithelial-to-mesenchymal transition(EMT).The effects of CSE on the phosphorylation of signal transduction and transcriptional activator 3(STAT3)were detected by Western *** cytometry was performed to investigate the effects of this proto-oncogene on cell cycle *** Inflammation caused by CSE was achieved in a lung-on-a-chip model with a mimetic *** exposure induced the degradation of intercellular connections and triggered the EMT *** exposure also activated the phosphorylation of proto-oncogene STAT3,while these effects were inhibited with *** CSE exposure in the lung-on-a-chip model caused activation of STAT3 in epithelial cells and endothelial ***0152,an inhibitor of activated STAT3,could be a potential treatment for CS-associated COPD and lung cancer.

摘要：宽带有机光电探测器(OPDs)可以集成到各种可穿戴设备中,在健康监测等领域显示出巨大的应用潜力.这里,我们以酞菁铅(PbPc)和富勒烯(C70)小分子分别作为给体和受体,基于MoO_(3)俘获电子辅助空穴隧道注入的机制实现了高性能宽带倍增型有机光电探测器(PM-OPDs).为了控制PbPc分子的晶相结构,我们分别制备了PbPc:C70体异质结(BHJ)和PbPc/C70平面异质结(PHJ)器件.可以看出,PHJ器件表现出更强的近红外吸收特性,即更有利于PbPc分子形成三斜相结构.我们进一步使用具有吸收互补特性的材料(PbPc和SubPc)作为有源层,采用PHJ/BHJ混合异质结结构,制备了在300–1000 nm范围内平坦的全色PM-OPDs.在-8 V反向偏压下,制得的全色PM-OPDs在整个光谱响应范围内的外量子效率都超过1000%.最后,我们在聚对苯二甲酸乙二醇酯基板上制备了柔性全色PM-OPDs,并成功地实现了人体脉搏信号的检测.本文通过设计器件结构和选择合适的材料,为获得高性能全色PM-OPDs提供了一种新策略.

摘要：The research on scroll profiles theory at present mainly is aiming at the single profile and its amelioration or parameter optimization,not aiming at the natural characteristic of the profiles equation of scroll profiles ***,the intrinsic differential equation bearing on arc-length and tangent direction angle was *** the inherent differential equation and general functional theory,the conversion ideas between the expression of intrinsic differential equation and the expression in Cartesian coordinate was studied,and the condition of involutes characteristic was *** detailed analysis of four typical scroll profiles was *** to the four typical scroll profiles and based on the method of Taylor series,the unified formation of general functional integration scroll profiles was established,which perfected general theory of scroll profiles *** envelope method to seek conjugation engagement profiles was *** unified general functional equation of scroll profiles represented the admissible function scrolls and the conjugation engagement characteristic of which was *** engagement condition of conjugation scroll profiles and the expression in Cartesian coordinate of conjugation scroll profiles of general functional integration scroll profiles were ***,the restriction of inherent characteristics of single scroll profiles model is broken *** modeling and machine tool path simulation can bridge the gap between design and manufacture which is essential for the design and manufacture of scroll *** this method a perfect solid model can be achieved,which leads to an optimal design in terms of quality,delivery time and *** presentation of unified formation of general functional integration scroll profiles represents foundation factor of instinct characteristics of scroll profiles,which widens the design method of scroll compressor for automobile air conditioning.

摘要：We have theoretically investigated two series of cyclometalated Pt(Ⅱ) complexes,a series [Pt(C,N,N) Cl] and b series [Pt(C,N,Npyrazolyl) Cl].The geometrical and electronic structures are calculated at the ECP60MWB//6-31G*(H,C,Cl,N,S) basis set level using DFT method;one-photon absorption(OPA) properties are calculated by using both TDDFT and ZINDO methods and two-photon absorption(TPA) properties are obtained with the ZINDO/SOS *** resonance integrals parameters(βsp and βd) for Pt are adjusted to -1 and -28.5 eV,respectively,to make max OPA wavelength calculated by ZINDO closest to the experimental data and TDDFT *** calculated results indicate the molecule 2b([Pt(Cnaphthyl,N,Npyrazolyl) Cl]) has the biggest potential as outstanding TPA materials because(i) the TPA properties of b series are more outstanding in IR wavelength range,the molecules in b series have good transparencies and possess 1-pyrazolyl-NH that is also available for another metal coordination(e.g.,dimerization) and chemical interactions;(ii) when C is Cnaphthyl in the C,N,N ligand of cyclometalated Pt(Ⅱ) complexes,the molecules have the best conjugation effect and the best TPA properties.

摘要：由于气隙磁场分布不均以及未建模动态性,数学模型不再适用于磁力轴承系统。基于错误数学模型的系统控制会表现出低响应和高颤动。为解决这一问题,本文提出一种三自由度混合磁轴承无模型自适应控制系统。该控制系统仅与控制电流和轴承的平衡位置有关。其参数估计算法的设计与模型无关,直接基于输入和输出数据的伪偏导数。本文通过不同直径的辅助轴承分析了三自由度混合磁轴承转子悬浮区域,以及通过两种不同的操作系统具体分析无模型自适应控制系统的可行性。模拟和实验结果表明,该三自由度混合磁轴承无模型自适应控制系统具有响应速度快,稳态误差小,和稳定性好等优势。

摘要：The type, model, quantity, and location of sensors installed on the intelligent vehicle test platform are different, resulting in different sensor information processing modules. The driving map used in intelligent vehicle test platform has no uniform standard, which leads to different granularity of driving map information. The sensor information processing module is directly associated with the driving map information and decision-making module, which leads to the interface of intelligent driving system software module has no uniform standard. Based on the software and hardware architecture of intelligent vehicle, the sensor information and driving map information are processed by using the formal language of driving cognition to form a driving situation graph cluster and output to a decision-making module, and the output result of the decision-making module is shown as a cognitive arrow cluster, so that the whole process of intelligent driving from perception to decision-making is completed. The formalization of driving cognition reduces the influence of sensor type, model, quantity, and location on the whole software architecture, which makes the software architecture portable on different intelligent driving hardware platforms.

摘要：The valuation of the hydraulic performance of a centrifugal pump with pre-whirl regulation of the inlet guide vanes was studied experimentally by varying the pre-whirl angle from -60° to 60° with distances between the inlet guide vanes and the impeller inlet of 280 mm, 380 mm and 460 mm. The efficiency-flow curves and the characteristic curves were obtained for the pump for various operation conditions. The experiment results demonstrated that the pre-whirl regulation widened the high efficiency zone and improved the hydraulic performance for off-design conditions with the proper pre-whirl angle. The axial distance between the inlet guide vanes and the impeller inlet influenced the pre-whirl regulation effect of the inlet guide vanes with the best pre-whirl regulation effect obtained for an axial distance of 380 mm. These results showed that an appropriate axial distance between the inlet guide vanes and the impeller inlet can improve the fluid flow at the impeller entrance with pre-whirl regulation for centrifugal pumps.

摘要：We propose an inverse method to determine the material parameters of a transparent device without any knowledge of the corresponding transformation function. The required parameters are independently obtained and expressed as functions of the introduced generator. Moreover, to remove the inhomogeneity and anisotropy of material parameters, a layered transparent device composed of only homogeneous and isotropic materials is presented based on the effective medium theory. The feasibility of using the layered device in antenna protection is also investigated. Full-wave simulation is carried out for verification. This work paves a new way toward designing metamaterial devices without specifying the underlying coordinate transformation, and has great guiding significance for the practical fabrication of transparent devices.

摘要：We compare the transport properties of electrons in monolayer graphene by modulating the Fermi velocity inside the barrier. A critical transmission angle is found only when the Fermi velocity in the barriers is larger than the one outside the barriers. It is shown that the transmission exhibits periodicity with the incident angle below the critical transmission angle, and attenuates exponentially in the opposite situation. For both situations, peak splitting occurs in the transmission as the number of the velocity barriers increases, and the characteristics of the transmission suggest an interesting application of an excellent band-pass filter. The dependence of the conductance on the Fermi energy through an identical velocity- modulation structure differs wildly with different Fermi velocities of the barrier. The counterpart of the peak splitting is the sharp oscillations in the conductance profile. Furthermore, some oscillations for the multiple barriers are so sharp that the structure may be used as an excellent sensor.